With all the rain and wet basements we've had this summer, it pays to take heed of possible mold problems. Use this primer to find out what to do to prevent mold growing.
Household mold has been linked to health problems, from asthma to neurological difficulties, and is unsightly and sometimes smelly.
Mold operates fairly simply. Preventing it is a matter of preventing excess moisture in your house, using the right building materials, and catching the problem before it requires large-scale intervention.
Mold is a natural and unavoidable part of life. “Mold spores are everywhere. We breathe them every day and it’s not a problem,” says Daniel Morrison, an editor at Fine Homebuilding magazine. “But if you can see it or smell it in your house, you have mold, and what that really means is: You have a moisture problem.” To survive, mold needs two things: moisture and a food source, such as dust. Even if the mold doesn’t affect your health, the source of the moisture should be located and fixed as soon as possible, before the water causes other damage, such as rot.
More households than ever are having mold problems today; the reason is not that mold is worse now than it was in the past, but that houses built in the last 25 years are not as moisture-resistant as your grandmother’s farmhouse. According to Morrison, houses are more energy efficient because they are tighter—they have fewer air leaks and that’s a good thing. But because they are tighter, they are also less able to tolerate bad construction details that result in water leaks. Moreover, the materials that they are built with are more refined so they are easier for mold to eat. Old building materials, such as solid wood and plaster, are hard for mold to eat, while today’s OSB and paper-faced drywall provide good foods for mold if they get wet.
And it’s not just building materials that allow mold to flourish. Mold can enter your home in a variety of ways and grow when moisture is present. Something as huge as a flood (mold is a major problem in post-Katrina New Orleans, for example) is a pretty obvious mold-enhancer, but there are many other causes of home dampness: plumbing leaks, air conditioning condensation, incorrectly installed window flashing, poor drainage around the exterior of your home, or incorrectly installed insulation, to name a few.
As for those health problems, both Morrison and Responsible Mold Solutions report that the majority of people affected are those with mold allergies, respiratory conditions like asthma, and weakened immune systems.
Mold management tips
“Mold is dramatically easier to get rid of the quicker you do it,” Morrison says. If you find mold, the first step is to find the source of the moisture—it could be as simple as making sure to use the exhaust fan in the bathroom.
If the mold is in a small enough area, it’s easy to wipe up with water and a little detergent. Just make sure you dry the area thoroughly afterwards. A mixture of bleach and water (no more than 1 cup bleach to 1 gallon of water) is also a good mold eliminator. Ventilate the area when you’re working and wear rubber gloves to protect your hands. NEVER mix bleach and ammonia.
If you suspect you have mold but it’s not visible, you might need to cut out a chunk of drywall to see if the problem is inside your walls. In this case, you may require outside help to get rid of the mold. Look in the yellow pages under “Mold inspection and renewal” to find a specialist. Some companies may advertise services to determine what kind of mold you have. “Some types of mold are not good to breathe,” Morrison says, “but having the mold tested is not important. Remediating it is.”
All houses should have good ventilation. If you think your house is prone to moisture, you can hire an inspector to look for trouble spots, inside and out. Small actions can make a difference: “Kitchens and bathrooms should have exhaust fans, and you should use them,” Morrison says.
Industry website www.responsiblemoldsolutions.org recommends covering crawl spaces to control moisture and keeping humidity at 40–60 percent. Air conditioners and dehumidifiers help, and if outside humidity isn’t too high, keeping windows open to increase airflow will also help. The website also suggests preventing condensation on cold surfaces by making sure to adequately insulate pipes, windows, roof, and exterior walls and floors.
Avoid carpets, especially in moist areas like basements. Even if moisture isn’t a primary concern, carpets act as traps for dust and other pollutants, including mold.
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